Senate Democrats, increasingly bullish on their 2020 chances, want no part of “Medicare for all” proposals being pushed by far-left populist presidential contenders.

Four recent polls show that a majority of Americans do not support the proposal, especially after finding out it would do away with their private health insurance.

Originally championed by Vermont Sen. Bernie Sanders and co-sponsored by fellow Democratic presidential primary contenders Sens. Elizabeth Warren of Massachusetts, Kamala Harris of California, Kirsten Gillibrand of New York, and Cory Booker of New Jersey, the “Medicare for all” legislation is seen as a loser proposal that could hurt down-ballot Democratic races in both chambers. Sanders, a socialist, appears to stand alone in his full-throated and enduring support of the policy.

But it’s a particularly sensitive area in the Senate, where Democrats are looking to end the Republicans’ 53-47 majority. That discomfort shows through in the reaction of Harris to questions about “Medicare for all,” having seemed to support it in response to a Democratic debate question, only to reverse course after.

“I don’t think it was any secret that I was not entirely comfortable — that’s an understatement,” Harris said at a recent stop in Iowa. “I finally was like, ‘I can’t make this circle fit into a square.’”

House Democratic leadership has steered clear of bringing a “Medicare for all” bill to the floor out of fear that it could hurt their members in swing districts and endanger their chances of keeping their majority in the chamber.

“I think it’s a losing message for 2020, and I think the Democratic presidential candidates have to realize that this is not a far-left country nor is it a far-right country,” New York Democratic Rep. Anthony Brindisi, a freshman lawmaker in a swing district, told reporters. “I think we’re all very vulnerable the further to the left some of the presidential candidates go.”

Senate Minority Whip Dick Durbin of Illinois recently told the Washington Examiner that nominating a candidate such as Sanders or Warren could “jeopardize” the party’s chances to winning over independent moderate voters in the general election. And Senate Minority Leader Chuck Schumer of New York has yet to support the “Medicare for all” proposal.

In Colorado, where Republican Sen. Cory Gardner is seen as vulnerable by Democrats this election cycle, “Medicare for all” is not widely accepted by the party faithful. Colorado Democratic Sen. Michael Bennet, another presidential primary candidate, has distanced himself from the proposal.

“How are you going to get it passed?” said the Nevada Democrat. “I think that we should focus on improving Obamacare. We can do that — without bringing something that would be much harder to sell. Improving Obamacare, people understand that. They would appreciate that. It locks in many important things.”

There’s some recent precedent to Democrats distancing themselves from the proposal.

During the 2018 midterm election, then-Arizona Democratic Rep. Kyrsten Sinema ran a successful Senate campaign and flipped a Republican seat while running in opposition to “Medicare for all.”

“I do not support ‘Medicare for all,’” Sinema told reporters at the time. “I’m really focused on solutions that are realistic and pragmatic and we can get done.”

Although Democrats are careful about how far Left they think their presidential nominee could affect their races, one strategist said it’s questionable how many seats are really in play, anyway.

“The anti-Trump voters are not voting Republican. The pro-Trumpers are not voting Left. The civil war created by the Trump movement continues and makes it highly unlikely for a major Senate shift. That does not mean the Democrats can’t pick up a seat. It means this is trench warfare,” veteran Democratic consultant Hank Sheinkopf told the Washington Examiner.